In vitro investigations of Staphylococcus aureus biofilms in physiological fluids suggest that current antibiotic delivery systems may be limited.

Orthopaedic surgical site infections, especially when a hardware is involved, are associated with biofilm formation. Clinical strategies for biofilm eradication still fall short. The present study used a novel animal model of long-bone fixation with vancomycin- or gentamicin-controlled release and measured the levels of antibiotic achieved at the site of release and in the surrounding tissue. Then, using fluids that contain serum proteins (synovial fluid or diluted serum), the levels of vancomycin or gentamicin required to substantially reduce colonising bacteria were measured in a model representative of either prophylaxis or established biofilms. In the in vivo model, while the levels immediately adjacent to the antibiotic release system were up to 50× the minimal inhibitory concentration in the first 24 h, they rapidly dropped. At peripheral sites, values never reached these levels. In the in vitro experiments, Staphylococcus aureus biofilms formed in serum or in synovial fluid showed a 5-10 fold increase in antibiotic tolerance. Importantly, concentrations required were much higher than those achieved in the local delivery systems. Finally, the study determined that the staged addition of vancomycin and gentamicin was not more efficacious than simultaneous vancomycin and gentamicin administration when using planktonic bacteria. On the other hand, for biofilms, the staged addition seemed more efficacious than adding the antibiotics simultaneously. Overall, data showed that the antibiotics' concentrations near the implant in the animal model fall short of the concentrations required to eradicate biofilms formed in either synovial fluid or serum.

First results from five multidisciplinary diagnostic centre (MDC) projects for non-specific but concerning symptoms, possibly indicative of cancer.

BACKGROUND: Patients with non-specific symptoms often experience longer times to diagnosis and poorer clinical outcomes than those with site-specific symptoms. This paper reports initial results from five multidisciplinary diagnostic centre (MDC) projects in England, piloting rapid referral for patients with non-specific symptoms. METHODS: The evaluation covered MDC activity from 1st December 2016 to 31st July 2018, with projects using a common dataset. Logistical regression analyses were conducted, with a diagnosis of any cancer as the dependent variable. Exploratory analysis was conducted on presenting symptoms and diagnoses of cancer, and on comparisons within these groupings. RESULTS: In total, 2961 patients were referred into the MDCs and 241 cancers were diagnosed. The pathway detected cancers across a broad range of tumour sites, including several rare and less common cancers. An association between patient age and cancer was identified (p < 0.001). GP 'clinical suspicion' was identified as a strong predictor of cancer (p = 0.006), with a reduced association with cancer observed in patients with higher numbers of GP consultation before referral (p = 0.008). CONCLUSIONS: The MDC model diagnoses cancer in patients with non-specific symptoms, with a conversion rate of 8%, demonstrating the diagnostic potential of a non-site-specific symptomatic referral pathway.

The genetic diversity of multiple sclerosis risk among Hispanic and African American populations living in the United States.

BACKGROUND: Substantial progress has been made toward unraveling the genetic architecture of multiple sclerosis (MS) within populations of European ancestry, but few genetic studies have focused on Hispanic and African American populations within the United States. OBJECTIVE: We sought to test the relevance of common European MS risk variants outside of the major histocompatibility complex (n = 200) within these populations. METHODS: Genotype data were available on 2652 Hispanics (1298 with MS, 1354 controls) and 2435 African Americans (1298 with MS, 1137 controls). We conducted single variant, pathway, and cumulative genetic risk score analyses. RESULTS: We found less replication than statistical power suggested, particularly among African Americans. This could be due to limited correlation between the tested and causal variants within the sample or alternatively could indicate allelic and locus heterogeneity. Differences were observed between pathways enriched among the replicating versus all 200 variants. Although these differences should be examined in larger samples, a potential role exists for gene-environment or gene-gene interactions which alter phenotype differentially across racial and ethnic groups. Cumulative genetic risk scores were associated with MS within each study sample but showed limited diagnostic capability. CONCLUSION: These findings provide a framework for fine-mapping efforts in multi-ethnic populations of MS.

Fluid consumption, exercise, and cognitive performance.

Laboratory evidence supports the notion that dehydration degrades exercise performance and impairs certain cognitive processes. The purpose of this study is to examine the effect of a voluntary versus a dictated drinking condition on exercise and cognitive performance. The study used a double-blind and paired design. Twenty male and female college students (10 women, 10 men) participated in an exercise protocol consisting of 1 hr of treadmill running followed by a high intensity portion continuing until voluntary exhaustion. The dictated drinking condition consisted of 900 ml of water equally distributed in 4 pre-prepared opaque bottles. At 15 min intervals the subject was instructed to drink the entire contents until the end of the 1 hr treadmill protocol. The voluntary drinking condition consisted of 225 ml of water within arm's reach of the subjects while on the treadmill. Exercise performance was significantly better (longer duration and faster speed) in the voluntary condition compared with the dictated condition. Cognitive test outcomes were not significantly different between drinking conditions. A difference in fluid absorption is a potential source of exercise impairment seen in the dictated fluid condition. The higher fluid consumption rate presumably would cause greater gastric and esophageal distention resulting in the diversion of blood flow from working muscles to the gastrointestinal system. In situations where dehydration is likely, drinking to recommended guidelines may protect individuals from dehydration and its negative effects. However, when dehydration is not likely, allowing an individual to follow voluntary drinking behavior is preferable for exercise performance.

Liquid foam improves potency and safety of gene therapy vectors.

Interest in gene therapy medicines is intensifying as the first wave of gene-correcting drugs is now reaching patient populations. However, efficacy and safety concerns, laborious manufacturing protocols, and the high cost of the therapeutics are still significant barriers in gene therapy. Here we describe liquid foam as a vehicle for gene delivery. We demonstrate that embedding gene therapy vectors (nonviral or viral) in a methylcellulose/xanthan gum-based foam formulation substantially boosts gene transfection efficiencies in situ, compared to liquid-based gene delivery. We further establish that our gene therapy foam is nontoxic and retained at the intended target tissue, thus minimizing both systemic exposure and targeting of irrelevant cell types. The foam can be applied locally or injected to fill body cavities so the vector is uniformly dispersed over a large surface area. Our technology may provide a safe, facile and broadly applicable option in a variety of clinical settings.

Common femoral arterial access and arteriography in infants: Principles, pearls, and pitfalls.

Infant femoral arterial access is an essential part of interventional procedures, hemodynamic monitoring, and support of critically ill patients. Due to small luminal diameter, superficial location, mobility, and increased risk of vasospasm, dissection, and thrombosis, femoral artery access in the infant is a technically demanding procedure. The purpose of this manuscript is to describe an approach to successful common femoral arterial access and arteriography in infants including common pearls and pitfalls.

Pedi-R-MAPP | the development, testing, validation, and refinement of a digital nutrition awareness tool.

BACKGROUND & AIMS: The Remote Malnutrition Application (R-MAPP) was developed during the COVID-19 pandemic to provide support for health care professionals (HCPs) working in the community to complete remote nutritional assessments and provide practical guidance for nutritional care. R-MAPP was adapted into Pediatric Remote Malnutrition Application (Pedi-R-MAPP) using a modified Delphi consensus, with the goal of providing a structured approach to completing a nutrition focused assessment as part of a technology enabled care service (TECS) consultation. The aim of this study was to develop and validate a digital version of Pedi-R-MAPP using the IDEAS framework (Integrate, Design, Assess and Share). METHODS: A ten-step process was completed using the IDEAS framework. This involved the four concept processes; Stage-1, Integrate (Step 1-3) identify the problem, specify the goal, and use an evidence-based approach. Stage-2, (Step 4-7) design iteratively and rapidly with user feedback. Stage 3, (Step 8-9) Assess rigorously, and Stage 4 (Step 9-10) publish and launch of the tool. RESULTS: Stage 1:Evidence-based development, Pedi-R-MAPP was developed using Delphi consensus methodology. Stage 2:Iteration & design, HCPs (n = 22) from UK, Europe, South Africa, and North America were involved four workshops to further develop a paper prototype of the tool and complete small-scale testing of a beta version of the tool which resulted in eight iterations. Stage 3:Assess rigorously, Small scale retrospective testing of the tool on children with congenital heart disease (n = 80) was completed by a single researcher, with iterative changes made to improve agreement with summary advice. Large scale testing amongst (n = 745) children in different settings was completed by specialist paediatric dietitians (n = 15) advice who recorded agreement with the summary advice compared with their own clinical assessment. Paediatric dietitians were in overall agreement with the summary advice in the tool 86% (n = 640), compared to their own clinical practice. The main reasons for disagreement were i) frequency of planned review 57.1% (n = 60/105), ii) need for ongoing dietetic review due to chronic condition 20.0% (n = 21/105), iii) disagreement with recommendation for discharge 16.2% (n = 17/105) and iv) concerns with faltering growth and/or need for condition specific growth charts 6.7% (7/105). Iterative changes were made to the algorithm, leading to an improvement in agreement of the summary advice on re-evaluation to 98% (p=<0.0001). CONCLUSION: A digital version of the Pedi-R-MAPP nutrition awareness tool was developed using the IDEAS framework. The summary advice provided by the tool achieved a high level of agreement when compared to paediatric dietetic assessment, by providing a structured approach to completing a remote nutrition focused assessment, along with identifying the frequency of follow-up or an in-person assessment.

Clonotypic structures involved in antigen-specific human T cell function. Relationship to the T3 molecular complex.

Monoclonal antibodies were produced against a human cytotoxic T cell clone, CT8III (specificity: HLA-A3), with the view of defining clonally restricted (clonotypic) surface molecules involved in its antigen recognition function. Two individual antibodies, termed anti-Ti1A and anti-Ti1B, reacted exclusively with the CT8III clone when tested on a panel of 80 additional clones from the same donor, resting or activated T cells, B cells, macrophages, thymocytes, or other hematopoietic cells. More importantly, the two antibodies inhibited cell-mediated killing and antigen-specific proliferation of the CT8III clone but did not affect the functions of any other clone tested. This inhibition was not secondary to generalized abrogation of the CT8III clone's function, because interleukin 2 responsiveness was enhanced. To examine the relationship of the structures defined by anti-clonotypic antibodies with known T cell surface molecules, antibody-induced modulation studies and competitive binding assays were performed. The results indicated that the clonotypic structures were associated with, but distinct from, the 20,000-mol wt T3 molecule expressed on all mature T lymphocytes. Moreover, in contrast to anti-T3, anti-Ti1A and anti-Ti1B each immunoprecipitated two molecules of 49,000 and 43,000-mol wt from 131I-labeled CT8III cells under reducing conditions. The development of monoclonal antibodies to such polymorphic T cell surface structures should provide important probes to further define the surface receptor for antigen.

Evidence Supporting a Phased Immuno-physiological Approach to COVID-19 From Prevention Through Recovery.

This paper presents an evidence-based strategy for improving clinical outcomes in COVID-19. Recommendations are based on the phases of the disease, because optimal interventions for one phase may not be appropriate for a different phase. The four phases addressed are: Prevention, Infection, Inflammation and Recovery. Underlying this phased approach is recognition of emerging evidence for two different components of pathophysiology, early infection and late stage severe complications. These two aspects of the disease suggest two different patterns of clinical emphasis that seem on the surface to be not entirely concordant. We describe the application of therapeutic strategies and appropriate tactics that address four main stages of disease progression for COVID-19. Emerging evidence in COVID-19 suggests that the SARS-CoV-2 virus may both evade the innate immune response and kill macrophages. Delayed innate immune response and a depleted population of macrophages can theoretically result in a blunted antigen presentation, delaying and diminishing activation of the adaptive immune response. Thus, one clinical strategy involves supporting patient innate and adaptive immune responses early in the time course of illness, with the goal of improving the timeliness, readiness, and robustness of both the innate and adaptive immune responses. At the other end of the disease pathology spectrum, risk of fatality in COVID-19 is driven by excessive and persistent upregulation of inflammatory mechanisms associated with cytokine storm. Thus, the second clinical strategy is to prevent or mitigate excessive inflammatory response to prevent the cytokine storm associated with high mortality risk. Clinical support for immune system pathogen clearance mechanisms involves obligate activation of immune response components that are inherently inflammatory. This puts the goals of the first clinical strategy (immune activation) potentially at odds with the goals of the second strategy(mitigation of proinflammatory effects). This creates a need for discernment about the time course of the illness and with that, understanding of which components of an overall strategy to apply at each phase of the time course of the illness. We review evidence from early observational studies and the existing literature on both outcomes and mechanisms of disease, to inform a phased approach to support the patient at risk for infection, with infection, with escalating inflammation during infection, and at risk of negative sequelae as they move into recovery.

Safety and feasibility of various fasting-mimicking diets among people with multiple sclerosis.

BACKGROUND: Fasting-mimicking diets have shown promise in experimental autoimmune encephalitis and are currently being investigated among people with multiple sclerosis (MS). Ensuring adherence to diet changes is critical to determining the efficacy of such interventions. OBJECTIVE: Our primary aim was to evaluate the safety and feasibility of several fasting-mimicking diets and investigate whether various levels of clinical support improve diet adherence among people with MS. Secondarily, this study evaluated the impact of fasting-mimicking diets on weight and patient-reported outcomes (PROs). METHODS: We conducted three pilot studies (two randomized controlled for 6 months; one randomized with transition to single arm) restricting either the amount or timing of calorie intake over 24 or 48 weeks. Interventions included calorie restriction (daily or intermittently) or time-restricted feeding. Adherence measures varied across studies but were collected at study visits along with weight and PRO data. RESULTS: A total of 90 participants enrolled; 70 completed the studies, with no serious adverse events reported. Overall adherence to the calorie restriction diets was poor. When participants were tasked with maintaining a diet in a pragmatic setting, neither previously completed intense clinical support and education, nor weekly electronic communication throughout the diet period appeared to improve diet adherence. Participants who were able to adhere to a calorie restriction diet predictably lost weight. In contrast to calorie restriction, adherence to a time-restricted feeding (TRF) diet was relatively good. No statistically significant changes in PROs were observed in an intention-to-treat analysis. CONCLUSION: The role diet may play in clinical outcomes in MS remains unknown, as class I evidence is lacking. Diet adherence remains a primary barrier to the feasible conduct of large, randomized controlled diet trials. Strict adherence to a TRF dietary change may be more feasible than calorie restriction and should be considered in future fasting-mimicking diet trials. ClinicalTrials.gov Registry:A Pilot Study of Intermittent Calorie Restriction in Multiple Sclerosis - NCT02647502. A Pragmatic Trial of Dietary Programs in People with Multiple Sclerosis (MS) - NCT02846558.

Fluvastatin and lovastatin inhibit granulocyte macrophage-colony stimulating factor-stimulated human eosinophil adhesion to inter-cellular adhesion molecule-1 under flow conditions.

BACKGROUND: Eosinophil accumulation in the lung is an important feature of airway inflammation in asthma. There is therefore much interest in developing novel therapies to prevent this process. Accumulating evidence suggests that statins have anti-inflammatory properties, including inhibition of leucocyte accumulation. We therefore assessed the ability of five statins to inhibit human eosinophil adhesion to recombinant human inter-cellular adhesion molecule (rhICAM)-1 under physiologically relevant flow conditions. METHODS: Purified eosinophils were pre-treated with a panel of statins before elucidation of the adhesion profiles of resting and granulocyte macrophage-colony stimulating factor (GM-CSF)-stimulated cells to rhICAM-1-coated microchannels at a flow rate of 0.5 dynes/cm(2). Images were recorded in real-time at 1 min intervals and analysed using Ducocell software. RESULTS: Fluvastatin and lovastatin (both 10 nm) significantly inhibited GM-CSF-stimulated eosinophil adhesion to rhICAM-1 after 2 min (34.4+/-3.0% inhibition and 37.8+/-12.6% inhibition, respectively, n=4, P<0.05) but had no significant inhibitory effect on unstimulated eosinophil adhesion. Mevastatin, simvastatin, and pravastatin (all 10 nm) had no significant effect on GM-CSF-stimulated eosinophil adhesion to rhICAM-1. A concentration range of fluvastatin and lovastatin inhibited GM-CSF stimulated eosinophil adhesion with significant (P<0.05) inhibition observed at low concentrations of 1 nm for both drugs. Mevalonate (100 nm) reversed fluvastatin-mediated but not lovastatin-mediated inhibition of eosinophil adhesion. CONCLUSIONS: Inhibition of eosinophil adhesion to ICAM-1 by fluvastatin and lovastatin under physiological shear stress represent novel actions by these drugs that may inform the development of anti-inflammatory therapy for allergic disease.

Estradiol shortens the period of hamster circadian rhythms.

Continuous administration of estradiol benzoate by means of subcutaneously implanted capsules shortened the free-running circadian period of locomotor activity of blind hamsters (Mesocricetus auratus) that had had their ovaries removed. Estradiol also advanced the phase of the wheel running of sighted female hamsters without ovaries that were entrained to a photoperiod with 12 hours of light and 12 of darkness. These results, and findings from hamsters undergoing natural estrous cycles, indicate that endogenous estradiol is involved in the regulation of circadian periodicity.

Identification of the receptor for antigen and major histocompatibility complex on human inducer T lymphocytes.

Human T cell clones and monoclonal antibodies directed at their surface structures were used to define the receptor for the antigen and major histocompatibility complex on inducer T lymphocytes. The results indicated that the receptor is a single complex consisting of the monomorphic T3 molecule with a molecular weight of 20,000 to 25,000 and a clonotypic disulfide linked heterodimer Ti with a molecular weight of 90,000. Sepharose-bound monoclonal antibodies (anti-Ti4 or anti-T3) to the receptor could activate clonal proliferation and inducer function for B cell immunoglobulin secretion and thus substitute for the appropriate combination of major histocompatibility complex gene product and specific antigen.

Knowledge, attitudes and behaviour regarding the infant oral health visit: are dentists in Ireland aware of the recommendation for a first visit to the dentist by age 1 year?

AIM: To assess the knowledge, attitudes and behaviour of dentists nationwide in Ireland regarding the infant oral health visit, and also to elucidate whether dentists were aware of the recommendation for a first dental visit by age 1 year and of what care should be provided at this visit. METHODS: A validated 10-item questionnaire was distributed to a representative sample of non-paediatric dentists (non-PDs) and paediatric dentists (PDs) practicing in Ireland. The questionnaire focused on respondents' demographics in addition to their knowledge, attitudes and behaviour regarding the infant dental visit. RESULTS: Seventy-three percent of non-PDs reported seeing patients aged 0-36 months. Compared to all PD respondents, 58% of non-PDs believed that the first dental visit should occur by age 1 year. Furthermore, non-PDs provided the same care as PDs at the infant dental visit, with the exception of evaluating for fluoride needs and placing fluoride varnish. The main barrier to early oral healthcare was reported to be parents not requesting dental appointments for their infants. CONCLUSIONS: There remains a need to increase the proportion of non-PDs in Ireland seeing infants by their first birthday. It is recommended that Irish undergraduate and continuing education courses incorporate clinical training regarding the infant oral health visit and emphasise fluoride needs evaluation and fluoride varnish application. Additionally, a nationwide health promotion initiative is indicated to inform parents of the importance of a dental visit by age 1 year.

TLR-mediated activation of type I IFN during antiviral immune responses: fighting the battle to win the war.

Toll-like receptors (TLRs) are crucially important in the sensing of viral infections and viral nucleic acids. TLR triggering leads to the induction of specific intracellular signaling cascades that result in the activation of two major families of transcription factors; the IFN-regulatory factors (IRFs) and nuclear factor-kappa B (NF-kappaB). IRFs and NF-kappaB work together to trigger the production of type I interferons (IFNalpha/beta) or inflammatory cytokines leading to the maturation of dendritic cells and the establishment of antiviral immunity. This review will focus on the most recent findings relating to the regulation of IRF activity by TLRs, highlighting the increasing complexity of TLR-mediated signaling pathways.

Informed consent for the study of retained tissues from postmortem examination following sudden infant death.

OBJECTIVE: To develop an approach for seeking informed consent to examine tissues retained from a previous study of sudden infant death syndrome (SIDS) as part of a study on asthma, and to document responses and participation rate. DESIGN: Pilot open-ended approach to 10 volunteer SIDS parents, followed by staged approach (newsletter, mail and telephone call) to seek consent from the target SIDS families for the asthma study. PARTICIPANTS: Parents (n = 10) of SIDS infants known to SIDS and Kids Victoria and parents of SIDS infants (n = 107) from the 1991-2 SIDS in Victoria case-control study. MAIN OUTCOMES: Qualitative responses of the piloted parents and study parents, and participation rates. RESULTS: The pilot group responses were used to refine the written material to be provided. Of the 72 families for which contact details were available, 45 gave verbal consent for contact by the Victorian Institute of Forensic Medicine regarding the asthma study, three refused and 24 did not respond to two letters. Thirty-three completed consent forms, all positive for participation in the asthma study, giving a positive response rate of 73% (33/45). CONCLUSIONS: The use of postmortem tissue for research is acceptable to the next of kin when an approach is sensitive to their concerns and needs and is made by experienced counsellors from a familiar organisation. Despite the painful memories evoked by the approach of the research group, the acceptance rate among those who could be contacted was high.

Activation of Stimulator of Interferon Genes (STING) and Sjögren Syndrome.

Sjögren syndrome (SS), a chronic autoimmune disorder causing dry mouth, adversely affects the overall oral health in patients. Activation of innate immune responses and excessive production of type I interferons (IFNs) play a critical role in the pathogenesis of this disorder. Recognition of nucleic acids by cytosolic nucleic acid sensors is a major trigger for the induction of type I IFNs. Upon activation, cytosolic DNA sensors can interact with the stimulator of interferon genes (STING) protein, and activation of STING causes increased expression of type I IFNs. The role of STING activation in SS is not known. In this study, to investigate whether the cytosolic DNA sensing pathway influences SS development, female C57BL/6 mice were injected with a STING agonist, dimethylxanthenone-4-acetic acid (DMXAA). Salivary glands (SGs) were studied for gene expression and inflammatory cell infiltration. SG function was evaluated by measuring pilocarpine-induced salivation. Sera were analyzed for cytokines and autoantibodies. Primary SG cells were used to study the expression and activation of STING. Our data show that systemic DMXAA treatment rapidly induced the expression of Ifnb1, Il6, and Tnfa in the SGs, and these cytokines were also elevated in circulation. In contrast, increased Ifng gene expression was dominantly detected in the SGs. The type I innate lymphoid cells present within the SGs were the major source of IFN-γ, and their numbers increased significantly within 3 d of treatment. STING expression in SGs was mainly observed in ductal and interstitial cells. In primary SG cells, DMXAA activated STING and induced IFN-ß production. The DMXAA-treated mice developed autoantibodies, sialoadenitis, and glandular hypofunction. Our study demonstrates that activation of the STING pathway holds the potential to initiate SS. Thus, apart from viral infections, conditions that cause cellular perturbations and accumulation of host DNA within the cytosol should also be considered as possible triggers for SS.

Hypercementosis Associated with ENPP1 Mutations and GACI.

Mineralization of bones and teeth is tightly regulated by levels of extracellular inorganic phosphate (Pi) and pyrophosphate (PPi). Three regulators that control pericellular concentrations of Pi and PPi include tissue-nonspecific alkaline phosphatase (TNAP), progressive ankylosis protein (ANK), and ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1). Inactivation of these factors results in mineralization disorders affecting teeth and their supporting structures. This study for the first time analyzed the effect of decreased PPi on dental development in individuals with generalized arterial calcification of infancy (GACI) due to loss-of-function mutations in the ENPP1 gene. Four of the 5 subjects reported a history of infraocclusion, overretained primary teeth, ankylosis, and/or slow orthodontic tooth movement, suggesting altered mineral metabolism contributing to disrupted tooth movement and exfoliation. All subjects had radiographic evidence of unusually protruding cervical root morphology in primary and/or secondary dentitions. High-resolution micro-computed tomography (micro-CT) analyses of extracted primary teeth from 3 GACI subjects revealed 4-fold increased cervical cementum thickness ( P = 0.00007) and a 23% increase in cementum density ( P = 0.009) compared to age-matched healthy control teeth. There were no differences in enamel and dentin densities between GACI and control teeth. Histology revealed dramatically expanded cervical cementum in GACI teeth, including cementocyte-like cells and unusual patterns of cementum resorption and repair. Micro-CT analysis of Enpp1 mutant mouse molars revealed 4-fold increased acellular cementum thickness ( P = 0.002) and 5-fold increased cementum volume ( P = 0.002), with no changes in enamel or dentin. Immunohistochemistry identified elevated ENPP1 expression in cementoblasts of human and mouse control teeth. Collectively, these findings reveal a novel dental phenotype in GACI and identify ENPP1 genetic mutations associated with hypercementosis. The sensitivity of cementum to reduced PPi levels in both human and mouse teeth establishes this as a well-conserved and fundamental biological process directing cementogenesis across species (ClinicalTrials.gov NCT00369421).